This page presents data, materials, and pre-registrations (saved as experimental protocols) for a research project examining relationships between chronological age and overconfidence. Abstract: This research investigated how different forms of overconfidence correlate with age. Contrary to stereotypes that young people are more overconfident, the results provide little evidence that overestimation of one’s performance or overplacement of one’s performance relative to that of others is correlated with age. Instead, the results suggest that precision in judgment (confidence that one knows the truth) is goes up with age. This result is strongest for probabilistic elicitations, and is not present in quantile elicitations or reported confidence intervals. The results suggest that a lifetime of experience, rather than leading to better calibration, instead increases our confidence that we know what we’re talking about.